TiVo MINI - Green Screen Reboot Loop

I could really use some help here.

I'm familiar with hard drive failures leading to TiVo green screens of death, but this is happening on a TiVo Mini, so there is no hard drive involved. For a long time now the TiVo Mini has been booting to the blue 'starting up' screen, then the black 'almost there' screen, but immediately lands on a green screen indicating a 'serious problem'. It's not exactly the same error as standard TiVo hard drive failure, but it does give the three hour fix...

TiVo MINI - Green Screen Reboot Loop

TiVo MINI - Green Screen Reboot Loop